220 likes | 410 Views
North American Drought Briefing For Jan & Nov 2007 to Jan 2008. Climate Prediction Center/NCEP/NOAA February 14, 2008 http://www.cpc.ncep.noaa.gov/products/Drought. Partners & Contributors. CPC: Kingtse Mo, Wanru Wu, Muthuvel Chelliah, Wesley Ebisuzaki, Yun Fan, Huug van den Dool, Wei Shi
E N D
North American Drought BriefingFor Jan & Nov 2007 to Jan 2008 Climate Prediction Center/NCEP/NOAA February 14, 2008 http://www.cpc.ncep.noaa.gov/products/Drought
Partners & Contributors CPC: Kingtse Mo, Wanru Wu, Muthuvel Chelliah, Wesley Ebisuzaki, Yun Fan, Huug van den Dool, Wei Shi EMC: NLDAS Team: Ken Mitchell, Youlong Xia, Jesse Meng, Helin Wei EMC: NAEFS Team: Zoltan Toth, Yuejian Zhu NASA/GSFC: Brian Cosgrove, Chuck Alonge Princeton Univ.: Eric Wood, Lifeng Luo, Justin Scheffield Univ. of Washington: Andy Wood, Dennis Lettenmaier Web Masters: Viviane Silva, Joe Harrison Project Funded by NOAA CPPA
P from Nov 2007-Jan 2008 California: Strong intraseasonal oscillations Southeast: Dec had some rain along the Gulf coast. No rain in Jan. Drought continues Texas and Southern Plains: Drought is developing Colorado: Rain in both Dec and Jan Nov 2007-Jan2008
SPI3: • The Northern central US is getting dryer • Texas: drought started to develop. • California had some rain ( so less dry) in comparison with last month. • In the long termSPI6 or higher Severe drought still exists in the Southeast including parts of Florida. Drought D0:SPI < -0.8 Moderate drought D1: -0.9 to -1.2 Severe drought D2: -1.3 to -1.5 Extreme drought D3: -1.6 to -1.9 Exceptional drought D4: SPI< -2 Ref: Svoboda et al. (2002)
Total SM percentile from RR (29-yr clim) Ensemble SM mean(10-yr clim) Southeast: dry Pacific Northwest: Wet Texas: getting dryer Ohio, northern Plains : wet Mosaic Soil moisture percentiles NASA (29-yr clim) Cosgrove and Alonge Noah
SM Percentiles at Different Levels Based on RR Drought D0:SM < 20% Moderate drought D1: 10-20% Severe drought D2: 5-10% Extreme drought D3: 2-5% Exceptional drought D4: <2% Ref: Svoboda et al. (2002) Texas and Dakota : dryness from 10cm to 1m, but into deep soil yet. Southeast: SM dryness to the deep level
Monthly Streamflow Conditions Southwest and mid-Atlantic states: dry Northeast and Ohio Valley: wet Southern Plains: getting dryer California: coast normal & inland dry
SRI3 and SRI 6 U. Washington – Andy Wood SRI3 Standardized runoff index SRI • In comparison with the SPIs, they all suggest: • Southeast: severe drought • Texas: drought started to develop (only appears in spi3 and sri3, not spi6 or sri6 longer) • SRI shows California drought. SRI6 1955-2005
Snow Water Equivalent (mm/day) NLDAS does not agree over the western mountain region: RR, Noah, VIC are positive and mosaic is negative All shows negative anomalies over the Northeastern region
Weekly precipitation 2-8 Feb 2008 More precipitation over the Pacific Northwest and Ohio Valley, the Southeast is still very dry Weekly soil moisture anom ensemble
Hot Spots • California: Rainfall does not entirely influenced by the cold ENSO signal because of the strong MJO. • Southeast drought: any relief in sight? • Texas and southern Plains: Will cold ENSO make it worse?
MJO and California Rainfall Cal PNW 150E
SSTs for Drought over the Southern Plains and the Southeast Pickup drought events based on SM percentiles over RFC10 (S-Plains) and RFC12 (Southeast) respectively Make the composites of SSTA based on events Cold SSTAs in the central Pac; Warm SSTAs in the Atlantic and the N-Pac Data source (SM) VIC 1915-2006 Andy wood SST ersst: 1915-2006
SSTAs for Jan 2008 The ENSO forecasts indicate that the cold ENSO event will continue for the next 3 months. The Atlantic SSTAs are decreasing (slowly since Nov).
Regional SM percentile Time Series Because the land-atmosphere coupling is strong over the Southern Plains, the drought events last longer in comparison with droughts over the SE . Using the VIC data (from 1915 on), we identify events 1917 May lasted 20 mos 1952 Jun Lasted 36 mos 1963 Apr lasted 16 mos Most recent one was 2005 lasted 9 mos
Regional total Soil moisture percentiles Time series Overall, the duration for droughts in RFC12 (Southeast) is shorter than droughts in the RFC10 area. The longest drought occurred in 1954. It lasted for 14 months
NAEFS Week1 and Week2 Fcsts Cold ENSO signal
CFS Downscaling Princeton U Jan 2008 Mar2008 Feb 2008 Forecasts started from Jan 2008
ESP Forecasts ENSO Based IC 20080203 Total SM Percentile Forecasts 1 month lead 3 month lead 2 month lead University of Washington - Andy Wood
Runoff Percentiles Forecasts ICs 20080210 1 month 3 months 2 months Southeast and Texas dryness continue for 1-2 months The upper Missouri basin will get dryer University of Washington - Andy Wood
Summary • Southeast: Drought is likely to continue. • California: The MJO has strong influence on rainfall. The convection related to the MJO does not in favor of rainfall in the next 15 days or so. • Pacific Northwest, the Northeast and the Ohio Valley: likely to be wet. • Drought is developing over the Southern Plains. • There is indication of dryness in south and north Dakota and part of Minnesota. • Areas needed to be monitored carefully: California and Southeast, Texas, Dakotas
Thanks for New Products • Brian Cosgrove and Chuck Alonge: Soil moisture percentiles based on 20+ year climatology (1979 on) from Mosaic and Noah • Andy Wood: SRI plots for runoff and SRI forecasts • Happy Valentine’s day!!!